1. Field of the Invention
This invention relates to a feeding roller, more particularly to a feeding roller for feeding a workpiece along a feeding route on a worktable of a wood working machine.
2. Description of the Related Art
A conventional feeding machine for feeding a workpiece along a feeding route on a worktable of a wood working machine generally includes a housing which is disposed above the worktable, and a plurality of feeding rollers which are mounted rotatably on a driven shaft that is driven by a motor. Each feeding roller includes a metal rim which is fixed on and which is rotated with the driven shaft, and a rubber sleeve which is sleeved on the metal rim so as to be in frictional contact with the workpiece placed on the worktable. When a workpiece of an irregular thickness is fed, the pressing force of the feeding roller applied to the workpiece is uneven, thereby resulting in deformation and bending of the workpiece. In addition, the rubber sleeve is susceptible to wearing and deformation, thereby resulting in shortened service life of the feeding roller and adversely affecting the feeding operation.
The object of the present invention is to provide a feeding roller which can feed a workpiece with an irregular thickness smoothly and evenly and which has a prolonged service life.
According to this invention, the feeding roller includes a hub member adapted to be rotated with a driven shaft and having a surrounding outer wall. A plurality of anchored seat members are disposed on the surrounding outer wall and are angularly displaced from one another. Each anchored seat member extends from the surrounding outer wall outwardly, and terminates at a distal outer end so as to define an anchored area between the surrounding outer wall and the distal outer end. A surrounding workpiece contacting member is disposed to surround and is spaced apart from the hub member, and includes an outer annular wall surface having a plurality of tangential points which are angularly displaced from one another. Each tangential point is adapted to be sequentially brought into frictional contact with the workpiece. When a respective one of the tangential points is brought into frictional contact with the workpiece, a reaction force is generated by the workpiece at the respective one of the tangential points and is directed toward the axis of the driven shaft. A plurality of force transmitting members extend from the outer annular wall surface inwardly and radially, and are angularly displaced from one another to bear the reaction force. Each force transmitting member includes a secured area which spacedly confronts and is ahead of a respective one of the anchored areas in one of clockwise and counterclockwise directions. When the outer annular wall surface is forced by the reaction force inwardly at the respective one of the tangential points, the secured area is moved towards the respective one of the anchored areas. A coupling and biasing member is interposed between the secured area and the corresponding anchored area such that rotation of the hub member is transmitted to the surrounding workpiece contacting member, thereby bringing the tangential points sequentially into contact with the workpiece, and such that the secured area is biased to move away from the corresponding anchored area.